1. Field of the Invention
The invention relates to a switch, more particularly to a tilt switch which is relatively small, is simple in construction and is easy to manufacture.
2. Description of the Related Art
Referring to FIG. 1, a conventional safety switch (A) comprises a switch casing (a) which has upper and lower sides that are respectively provided with switch terminals (b, c). A movable switch contact (d) is provided inside the switch casing (a) between the switch terminals (b, c). The force of gravity which acts on the switch contact (d) is used to pivot the same to connect electrically with one of the switch terminals (b, c).
The safety switch (A) is usually installed in an electrical device, such as an electric fan. When an electric fan incorporating the safety switch (A) is in an upright position, the switch contact (d) electrically connects with the switch terminal (c) so as to achieve a close circuit condition. When the electric fan is accidentally toppled, the switch contact (d) pivots away from the switch terminal (c) so as to connect electrically with the switch terminal (b) and therefore achieve an open circuit condition.
The drawbacks of the above disclosed safety switch (A) are as follows:
1. Note that the safety switch (A) employs a pair of switch terminals (b, c) which are spaced apart so as to permit movement of a switch contact (d). The safety switch (A) is relatively complicated in construction and has a relatively large size. Assembly of the safety switch (A) requires a certain degree of precision so as to ensure proper operation of the same. Attainment of such precision requires expensive machinery and highly experienced workers, thereby increasing the manufacturing costs of the safety switch.
2. The switch contact (d) is pivoted onto the switch casing (a). Rust easily occurs at the pivot joint of the switch contact (d) and can hinder the proper operation of the safety switch (A).
3. The force of gravity is used to move the switch contact (d). If the switch contact (d) is relatively light in weight, effective pressing action of the switch contact (d) against either one of the switch terminals (b, c) cannot be achieved. Breakage of the switch terminals (b, c), however, can easily occur if the switch contact (d) is relatively heavy.